In general, conventional processes for producing cream cheese starts from fat-adjusted milk, for example a combination of usually pasteurized raw milk or skim milk with cream. The process typically comprises the following steps:
pasteurizing and homogenizing the milk blend,
fermenting the milk blend with lactic acid bacteria,
separating the fermented product into a curd fraction and a whey fraction and removing the whey fraction,
optionally adding further liquid or solid (powdery) cream cheese ingredients, such as salt, stabilizers, flavoring agents, sweet whey powder, and sweet or sour cream, to the curd fraction,
heating and homogenizing the resulting mixture, and
filling and packaging the resulting cream cheese.
In the dairy field, centrifugation is one major method for separating dairy products into fractions according to their specific gravity. For example, milk can be separated into a high-fat cream fraction having a relatively lower density and a low-fat skim milk fraction having a relatively higher density. More recently, membrane separation technologies such as microfiltration, ultrafiltration, nanofiltration and reverse osmosis have been introduced for fractionating dairy products according to the particle size and/or molecular weight of their respective components.
For example, US 2010/0098820 A1 discloses the use of a microfiltration membrane to concentrate skim milk, providing a relatively low whey protein/casein ratio in the obtained concentrated milk. Likewise, WO 2009/059266 A1 describes a process for the production of casein, comprising a step of subjecting skim milk to microfiltration to provide a retentate having a high casein content and being useful for cheese making.
WO 99/37162 A1 relates to a method for preparing cheese, inter alia comprising a step of concentrating milk by means of reverse osmosis or nanofiltration in combination with ultrafiltration and optionally diafiltration and/or microfiltration to produce a concentrated milk having an increased casein content.
EP 2 269 466 A2 describes a method of making a high fat cream cheese product from a standardized milk base using lactic acid bacteria fermentation. The fermented milk base is subjected to ultrafiltration to form a retentate and a permeate wherein the retentate has a fat content which is higher than that of the standardized milk base.
EP 1 752 046 A1 describes a method for producing concentrated and fermented dairy products, in particular cream cheese, inter alia comprising a step of separating fermented process milk by means of microfiltration into an acidified permeate and an acidified retentate, which acidified retentate is further processed into the desired dairy product. Likewise, U.S. Pat. No. 4,897,277 describes the use of microfiltration to separate curd from whey.
WO 96/35336 A1 describes a process for producing whey protein concentrate using an ultrafiltration step to remove water and small water-soluble molecules from whey.
WO 99/40798 A1 describes a process for producing a whey salt powder, wherein whey or an ultrafiltration permeate of milk or whey is subjected to nanofiltration, and the obtained permeate is further concentrated by evaporation or a combination of reverse osmosis and evaporation and dried.
Despite the prior description and use of membrane separation technology in the dairy field, the application of such technology has focused on specific, separate aspects of the cheese making process only, rather than considering the cheese production as a whole. In particular, it must be emphasized that a membrane separation process will usually provide two fractions, namely a retentate and a permeate. However, the prior art application of membrane separation technology has mainly focused on producing one fraction which can be used or provided in a beneficial manner, without considering options for using the remaining other fraction. In addition to such considerations, it has been observed that there is still room for improvement in the manufacture of cream cheese in terms of flavor and texture properties of the final product.
In view of the above, it may be desirable to provide a process for producing cream cheese and related products from dairy and dairy fractions, allowing to better tailor, standardize and control the composition and properties of the final cream cheese, including its flavor and texture. In addition, it may be desirable to provide a process for producing cream cheese and related products which allows for better and more complete use of the starting dairy, including its major fractions such as casein, whey protein, fat, lactose and minerals. The process for producing cream cheese and related products may be extended to a process for preparing a food product, namely by combining the resulting cream cheese with one or more additional food product components. Finally, it may be preferable to provide cream cheese with unique sensory properties, at the same or a reduced fat content as compared to conventional cream cheese.